Container opening provision and method of making same



Jan. 5, 1965 s. A. FREESE 3,16

CONTAINER OPENING PROVISION AND METHOD OF MAKING SAME Original Filed Jan. 2, 1962 2 Sheets-Sheet l unllllljllg;

FIGY.I.

' INVENTOR SAMUEL A. FREESE BY M,Mx

ATTORNEYS.

United States Patent Ofilice 33211;

3,1M,ll7tl CONTAINER OPENING PROVISION AND METHOD OF MAKING SAME Samuel A. Freese, Warson Woods, Mo., assignor to Container Corporation of America, Chicago, 111., a corporation of Delaware Original application Jan. 2, 1962, Ser. No. 163,757, now Patent No. 3,093,293, dated June 11, 1963. Divided and this application Mar. 28, 1963, Ser. No. 268,790 9 Claims. (Cl. 93-94) This. invention relates to opening provisions for containers and the like, and is particularly concerned with the method of its manufacture. The structure of the opening provision is disclosed and claimed in parent application, Serial No. 163,757, filed January 2, 1962, now Patent No. 3,093,293, issued June 11, 1963, of which this is a divisional application.

A preferred opening provision for containers will be disclosed in connection with fibre body containers constructed with a so-called easy opening tear means which assists in breaking at least one container wall ply so that the final opening operation is reduced to breaking an inner wall which is provided with a joint defining the line of final opening which extends about the circumference of the container body and substantially from end to end. Fibre body container requires a certain degree of strength to retain the contents and hold up under normally rough handling. This is particularly true of containers when filled with a product capable of generating pressure outwardly on the walls of the body, such products including biscuit dough which is under refrigeration.

Therefore, it is an important object of this invention to provide a container having easy opening means for breaking the body wall, but which is strong and rugged to withstand internal pressure, rough handling and the effects of moisture from refrigeration storage.

It is also an important object of this invention to provide a container with means for quickly and easily opening the same and one which may be operated by manual manipulation without the assistance of opener devices of any kind.

A further object of this invention is to provide a novel method of manufacturing a container with easy opening provisions on a continuous basis and with relatively simple apparatus which will result in accurate timing of the various operations to produce good results on an economical basis.

Other objects of this invention will be disclosed or will appear from the following description which relates to a preferred example of a container and apparatus adapted for its continuous manufacture.

In this connection, the container comprises a foil liner adhesively secured to an inner ply of fibre or paper material which, in turn, is adhesively secured to an outer ply of fibre or paper material. The outer ply is covered by a label ply of foil or other suitable material, and easy opening means is disposed between the inner and outer plies in predetermined relation to a joint formed in the inner Wall ply. The container formed in this manner is provided with a pull tab which includes the easy opening means and the outer ply and label, and the tab is formed by suitably slitting these plies after the plies have been combined into a layer for winding on the mandrel of a suitable wind'ing machine. The slitting of the tab involves a unique operation which produces a tab opening for improved access to the tab itself, such operation being performed in conjunction with the slitting operation and in advance of an operation for inserting reinforcing means under the layer in which the tab is formed.

The invention further consists in the structural features and steps in the method of manufacturing a container 7 which will be hereinafter described in detail, and with reference to the accompanying drawings, wherein:

FIG. 1 isa fragmentary elevational view of a container provided with the improved opening means;

FIG. 2 is a greatly enlarged sectional view of a fragmentary portion ofthe container seen at line 2-2 in FIG. 1;

FIG. 3 is a schematic plan view of the winding apparatus by which the container may be manufactured in a continuous process; 5

FIG. 4 is a further schematic view in elevation of another portion of the apparatus;"

FIG. 5 is an exploded perspective view of means for cutting and forming the tab opening means;

FIG. 6 is a sectional elevational view ofthe tab forming means herein preferred, the viewbeing taken at the beginning of the tab slitting operation;

FIG. 7 is a view similar to FIG. 6, but showing a further stage in the tab slitting and folding operation; and

FIG. 8 is still another view similar to FIG. 6 showing the folding operation in a final stage. i

With reference to FIGS. 1 and 2, the container isseen to include a body 10 closed at one end by a suitable member 11 crimped on the body wall. The opposite end is also closed, usually after the contents has been inserted, by a similar member 12 which is also crimped on the body wall. The body 10 is composed of an inner layer A of multiple plies, an outer layer B also of multiple plies and a tear means T disposed between layers A and B extending spirally about the body 10 between the end closure members 11 and 12 for substantially one turn or 360. In forming the container body It) on a spiral winder apparatus depicted generally schematically by the mandrel M in FIG. 3, a pull tab 13 is formed by making parallel slits or cuts 14 in layer B and cross cutting the layer at 15 between the slits 14. The cut 15 exposes a starting end of a strip of the layer B by which the layer may be torn down spirally of the body 10 to effect the opening of the container. In order to gain greater access to the starting end 15 of the tab 1.3, a portion of the layer B is turned or folded back upon itself at 16' thereby forming an easily seen gap or space S in the layer B. The space S is slightly wider than the tear means T, as shown in FIG. 1, thereby forming a recess for easy access to the end 15 which may be lifted up along the parallel slits 14. The raised tab 13 initially bends or folds approximately at the point 17 (FIG. 2) and is of suitable length to permit a secure grasp thereof for subsequent pulling to tear the layer B in the direction of the means T.

The starting end tab13 formed as described above would exposea portion of the body inner wall A, except for the presence of a strengthening patch or ply 18 which is secured between the layers A and B to maintain wall strength in the area of the slits 14 and 15 and space S. From the foregoing description it can be appreciated that the container body 10 is provided with a unique tear tab structure which does not materially weaken the wall strength and results in a much more easily openable container than heretofore found on the market.

The advantages are quite evident and the structure thus provided is an improvement on the character of easyopen container disclosed and claimed in the prior application of Donald V. Hanlon, filed November 9, 1959 and bearing Serial No. 851,799, now Patent No. 3,051,- 370, issued August 28, 1962. The method of manufacturing the present container is also an improvement over the container disclosed and claimed in the prior application of David I. OSullivan, filed November 9,1959 and bearing Serial No. 851,887. A more complete understanding of certain methods of manufacturing the container of FIG. 1 herein may be had by reference to said prior applications, but it will be sutficient for present purposes to refer to FIGS. 3 and 4 of this application for details of structure and method.

In FIG. ,3 the winding apparatus schematicallyillustrated by the mandrel M is fed with the layers A and B, and the usual belt device (not shown) of such apparatus furnishes the required movement of layers A and B to and about the mandrel. The resulting stick of containers advances along the mandrel in the direction of arrow 19 to a suitable cut-off device not necessary to show. The layer A consists of a suitable paper backed foil liner ply 20 and a ply 21 of Kraft paper of approximately .015 thickness. The ply 21 is fed onto the mandrel M such that its edges 21a is butted with the adjacent and a suitable label ply 23. As the respective wall ply 22, tear means T and label ply 23 are fed to the mandrel M, the means T is disposed beneath the ply 22 and the label ply 23 is disposed on top of ply 22 with a margin 23a extending therefrom to provide an overlap on the exterior of the container body 10 for sealing the body against moisture attack. The wall ply 22 is arranged to form a butt joint at the margin 22a, such butt joint being off-set from the butt joint in the inner wall ply 21. During the advance of layer B and after the plies 22 and 23 and tear means T have been brought together in the desired superposed relation, a tab slitting operation is performed at station C and a patch applying operation is performed at station P. At station C the slitting operation forms the parallel cuts 14 and the crosscut 15 in a U-shaped pattern. The slitting at 14 is alongside the means T and through the plies 22 and 23, whereas the cross-cut 15 is through the plies 22 and 23 and through the means T. At the same time and during the slitting operation the fold 16 is formed so that the space S is established. As the layer B advances to station P suitable means is provided for forming a patch 18 from a strip of patch material 18a (FIG. 4) and for applying the patch under the area containing the cuts 14 and 15 and the space S. The prepared layer B then moves to the mandrel M and is superimposed on layer A.

Further understanding of the herein preferred method of manufacturing container body 10 may be had upon reference to FIG. 4. As there is shown in a schematic manner, it can be seen that the wall ply 22 passes through an adhesive bath or applying means 24 which applies adhesive to both faces of the ply through the action of rollers 25 and 26. The ply 22 then moves to the combining rolls 27 and 28 where the means T is joined at the under face of ply 22 and adheres thereto. It is a feature that means T acts to kill the adhesive in the narrow strip established by the means T so that when the layer B reaches the layer A on the mandrel there will be no adherence between plies 21 and 22 where the means T is positioned. This permits the means T to readily lift from the ply 21 when the container is opened.

The label ply 23 also moves to the combining rolls 27 and 28 and is adhered to the upper face of ply 22, a sulficient amount of adhesive spreading onto the extended edge 23a to provide for securing such edge 23a in sealed and lapped relation. The thus combined layer B moves from rollers 27 and 28 to station C where the slitting or cutting is performed in a predetermined manner. Station C is provided with a rotary slitting backup roll 29 having a projecting portion 30 formed with a relief slot 31 which defines a cross-cut edge 32 and parallel side edges 33 more particularly shown in FIGS. 5 to 8. The back-up roll 29 cooperates with a cut-ting roll 34 on which a cutter element 35 is carried. The element 35 has a concavely formed cutting face 36 which cooperates with the edges 32 and 33 of the recess 31 in roll 29 to form the cut lines 14 and 15.

Further advance of the layer B toward mandrel M brings the cut area into station P where reinforcing patches 18 are applied. In this station the layer B is backed up by a suction lift device 37 which draws the patch 18 upwardly, since the layer B has been slit at 14 and 15 by this time. A patch applying roll 38 brings each patch 18 up to the moving layer where it is picked off the roll by the suction effect of device 37 at the top surface of the layer B. The roll 38 operates in conjunction with a second roll 39 to cut patches 18 from the strip 18a which is fed by the powered roll 40 adjacent a stationary table 41.

FIG. 4 includes a schematic illustration of one form of control for the operations to be performed at stations C and P, such control being regulated and timed by the presence of indicia or spots 42 carried on thelabel ply 23. The spots 42 are sens-ed by a suitable electric eye device 43 having the usual projector 44 arid receiver 45 which are activated by the spots 42 as they reach the control zone of the device 43. Electrical power from a suitable source 46 is connected by lead 47 to the device 43 and lead 48 connects the device 43 with motor means 49 which drives a suitable geared drive 50. The other side or lead 51 is connected to a switch device 52 for energizing the apparatus. Power from the drive 51) is supplied by a shaft 53 to the roll 34 which also dri'v'es roll 29, arid other shafts 54 and 55 are connected to the rolls 38 and 39 respectively. A drive take-off shaft 56 connects rolls 3% and 40. While the foregoing disclosure is schematically presented, it is obvious that any suitable drive system may be employed for the purposes expressed herein. 1

The device 43 is periodically activated by each indicia or spot 42 and likewise the devices in stations C- arld P are periodically activated to complete the described 11110" tions in such timed relation that a tab 13 is formed station C and a patch is cut and applied at station P.

The periodic operation is quite accurate as the printing of the label ply with the spots 42 can be accurately es tablished for spacing of the spots 42 with one to each complete container as predetermined by the length of each container. While not shown, it is obvious that a cut-off device may be disposed at the discharge end of mandrel M and accurately controlled by the device 43 to cut the continuously formed stick into the individual container bodies.

A feature of this invention resides in the forming of the tab 13 and space S such that the container body 147 may be more easily opened without structurally weaken ing the wall strength. FIGS. 5 to 8 inclusive will provide an adequate understanding of the same and reference will now be had to such views. FIG. 5 is a perspective view of the tab cutting or slitting means with the members 29 and 34 slightly exploded to show the details more clearly. Thus, member 29 is composed of a sandwich of parts 29a, 29b and 290 suitably secured together and mounted on a shaft 29d. The parts 29:: and 290 are each provided with a projection 30a and 30c which projects to form side cutters along the peripheral edges. The central part 2% serves to hold the parts 2% and 290 in properly spaced relation, and also is formed with a partial projection 30 which corresponds to the contour projection 313a or 300, but is cut away at 31 to form a' recess shown in broken outline in FIG. 5 at R. The wall 31 of the recess R terminates in a cutting edge 32 which: is directed transversely of the side cutting edges formed between projections 30a and 300. suitably secured on a shaft 29d and is rotated in accordance with the disclosure of FIG. 4. The cooperating rotating member 34 is made up of a sandwich of parts 34a, 34b and 34c suitably secured together and mounted on a shaft 34d. The parts 34a and 340 are clamping The member 29 is members which secure the central part 34b in position such thatvthe projecting cutterelement 35 extends beyond the circular periphery of the parts and is located opposite the recess R in the member 29. The cutter element 35 is provided with a slightly concaved cutting face 36, in which the concavity conforms substantially to the curvature of the side cutting edges of projections 30a and Site. The cutter element 35 thereby is dimensioned to pass into the recess R beginning adjacent the transverse cutting edge 32 of such recess. As is seen in FIGS. 4 and 5, the drive shaft 53 rotates member 34 through connection with the shaft 34d, and shaft 34d is connected to shaft 29d through a gear train including the gears-60, 61, 62, and 63, although it is at once apparent that any other drive arrangement may be utilized in order to rotate members 34 and 29 at the same speeds so that the cutter elements 35 will be properly timed to pass into respective recesses R and effect the desired cut in the layer B which is fed therethrough. It is, of course, appreciated that the cutter element 35 and the side cutter projections 36a and 3th cooperate to form the parallel cuts 14 and transverse cuts as shown in FIG. 1 or 3.

Turning now to FIGS. 6, 7, and 8 it can be seen that FIG. 6 illustrates the cutting action of members 29 and 34 at an initial stage, and FIG. 7 illustrates a more advanced stage of the cutting operation in which the parallel cuts 14 and the transverse cuts 15 have been completely formed so that the cutter element 35 extends into the recess R of member 29. At the stage of the operation shown in FIG. 7, the layer B in the Zone of the transverse cut 15 is beginning to form the fold 16 at the trailing margin of the cutter element 35. Now referring to FIG. 8 it can be seen that the members 29 and 34 have passed to a point where the cutter element 35 has left the recess R, but is still in engagement with the layer'B so that fold 16 has been moved nearer to its final folded position, thereby forming the gap space S shown in FIG. 2.

In order to have the members 29 and 34 operate in the manner just described, and without causing excessive damage, tearing, or stressing of the fibre or paper material in the layer B, ithas been found that the linear speed of the layer B needs to be slightly faster than the linear speed of the members 29 and 34 as measured at the peripheral surface of the cutting projections a and 36c. As an example of a successful operation, applicant has obtained good results by moving the layer B at a speed of 125 feet per minute, and rotating the members 2% and 34 at a speed of 100 feet per minute where the dimension D is three inches. At these speeds, the layer B will be caused to slip on the face surface of projection 3t relative to the cutter element 35, thereby causing the portion of the layer following the trailing edge of the element to fold back upon itself at 16. The rotation of the members 29 and 34 is sufiiciently fast so that the pull on the layer B from the mandrel M is not resisted by the slower speed of the cutter element 35 long enough to create eX- cessive stress or tearing action therein. On the other hand, the trailing surface of the cutter element 35 remains in contact with the fold 16 long enough to cause it to fold substantially completely back upon itself to the position illustrated in FIG. 2.

It should now be appreciated that the members 29 and 34 perform the functions of cutting the layer B along the parallel lines 14 and along the transverse lines 15, and cutter element 35. simultaneously forms the fold 16 to provide the gap space S. This operation is performed prior to the layer B moving to station P where the reinforcing patch 18 is cut from a continuous supply strip 18a between co-acting members 38 and 39 with the member 38 being provided with suitable means to retain each cut patch 18 on its periphery during transfer of the patch 18 upwardly under the adhesively coated surface of the layer B at the back-up rolls 37. The adhesive contact established with the patch 18 at roll 37 easily withdraws the patch from the member 38. The rolls 38 and 39 are provided with suitable cutting means (not necessary to show) for chopping the strip 18a during rotation. The patch 13 thusformed is held on the roll 38 by vacuum drawn in passage 38a through the axial passage 38b in the roller shaft 54. The passage 33b is connected to a suitable vacuum pump (not necessary to show) and controls which break the vacuum at about the time the patch 18 has touched the adhesive coating under layer B are provided to regulate the operation as indicated.

The layer B with the now applied patch 18 under the cut lines 14 and 15 and covering the gap space S at the fold 16 (FIG. 2) is wound on the mandrel M upon the layer A. The registration of layers A and B is arranged such that the butt joint in layer A at the margin 21a is substantially under the tear means T when layer B is wound over layer A. It should also be appreciated that the usual winder belt means, such as disclosed in the OSullivan application Serial No. 851,887, now Patent No. 3,051,379, will compress the layers A and B and crease the fold to so that it will lie substantially flat in the surface of the container body.

The slitting station C and patch applying station P are spaced apart a distance equal to the length of layer B required to make one complete container body lit, although the spacing could be any multiple of such body length. It has been pointed out that theoperations taking place at stations C and P are controlled by the scanning device 43 in response to the spots or indicia 42 carried by the label 23. Thus the means in each station C and P operates intermittently while the layer B moves continuously therethrough.

While the foregoing description has been given in connection with a container body construction comprising essentially two layers in its wall, with each layer made up of several plies, it is understood that the layers may be of any suitable composition without regard for the number of plies. For example, it is possible to have a label strip of sufficient strength and composition to eliminate the separate strip 22 (FIG. 3) and run the tear means T directly under the label. It is contemplated that the layers A and B may have different thicknesses and strengths so that the inner layer will be strong when combined with a lightweight label, but relatively vulnerable to inwardpressure when the butt joint of the inner layer is exposed. Other variations and combinations of structure will be brought to mind after understanding the I foregoing details of this invention, and it is the aim herein to cover all such variations and combinations in the appended claims.

What is claimed is:

l. A method of making a container body with tear to open means simultaneously built thereinto during the winding step, said method including the steps of winding an inner wall layer in a spiral winder, winding an outer wall layer over said inner wall layer, and prior to winding said layers together, feeding a tear means upon the outer wall layer, forming a starting pull tab in said outer wall layer and in said tear means, and exposing the end of the pull tab by folding a portion of said outer wall layer to form a gap space in said outer wall layer.

2. A method of making a container body with tear to open means formed therein during the making of the body, said method including the steps of winding a first layer in a spiral with a margin in butted relation to form a butt joint in such layer, feeding a second layer upon said first layer to cover the butt joint, forming a pull tab in said second layer by cutting along parallel lines joined at corresponding ends by a transverse cut line, and exposing an end of the tab at the transverse out l ne by folding said second layer at the transverse out line in a direction away from the tab end to be exposed.

3. A method of forming a pull tab in a web of material to be embodied in articles of manufacture which is torn to open, said method including feeding the web toward the point of its embodiment in the article, passing said 7 web between cooperating cutter members which form the tab by spaced parallel slits and a transverse slit joining the parallel slits, and operating said cutter members at a rate different from the feed rate of the web such that a portion of the web material adjacent the transverse slit is folded.

4. A method of forming a tear starting tab in a tearable web comprising the steps of feeding the web at a predetermined linear speed, providing a first rotary cutter member at one side of the web and a second rotary cutter member at the opposite side, driving said members at a lesser speed and utilizing one of said members to create a cut transverse to the direction of web feed and to fold a portion of the web adjacent the transverse cut backwardly relative to the direction of Web feed.

5. A method of constructing an easy-opening spiral Wound container body consisting in winding an inner wall layer with a butt joint between the turns thereof, combining an outer wall layer and a tear means in advance of winding the combination on the inner wall layer, forming a pull tab in the outer wall layer to include the tear means, exposing an end of the pull tab by back-folding a portion of the outer wall layer and the tear means, and winding the outer wall layer and tear means combination onto the inner wall layer with the tear means aligned upon the butt joint in the inner wall layer.

6. A method of constructing an easy-opening spiral 'WOUIlCl container body consisting in winding an inner wall layer with a spirally directed butt joint therein be tween the turns thereof, feeding an outer wall ply through an adhesive applicator to deposit adhesive on the outermost and innermost surfaces thereof, combining a label ply on the outermost surface of the outer wall ply and a tear means on the innermost surface, forming a pull tab in the combined label and outer wall plies to include a portion of the tear means and substantially simultaneously exposing an end of the pull tab by back-folding the combined plies and tear means in an area aligned with the pull tab, and winding the combined plies and tear means onto the inner wall layer to adhesively unite the same with the tear means aligned upon the butt joint.

7. A method of constructing an easy-opening spiral wound container body consisting in winding an inner wall layer with a spirally directed butt joint therein between the turns thereof, preparing an outer wall ply with adhesive on its innermost and outermost surfaces, com- ,bining the thus adhesively coated outer wall ply with a label ply on its outermost surface and tear means on its innermost surface, using the tear means to kill a strip of the adhesive coating on the innermost surface of the outer Wall ply, forming a pull tab in the combined outer wall and label plies and in the tear means and exposing an end of the pull tab by folding a poition of the combined plies and tear means away from the pull tab, and winding the combined plies and tear means onto the inner wall layer with the tear means aligned upon the butt joint to adhesively unite the inner wall layer and the outer wall ply except where the adhesive is killed by the tear means.

8. A method of constructing an easy-opening spiral wound container body consisting in winding an inner wall layer with a spirally directed butt joint therein between the turns thereof, preparing an outer wall ply with adhesive on its innermost and outermost surfaces, combining the thus adhesively coated outer wall ply with a label ply on its outermost surface and tear means on its innermost surface, using the tear means to kill a strip of the adhesive coating on the innermost surface of the outer wall ply, simultaneously cutting through the combined outer wall and label plies and the tear means to form a pull tab and a back-folded portion spaced from an end of the pull tab, and winding the combined plies and tear means onto the inner Wall layer with the tear means aligned upon the butt joint to adhesively unite the inner and outer walls except where the adhesive is killed by the tear means.

9. A method of forming a pull tab in a web of material to be embodied in articles of manufacture which is torn to open, the method including continuously feeding the web toward the point of its embodiment in the article, passing the web between cutting means which forms the tab, operating the cutting means intermittently and at a rate different from the feed rate of the web such that a portion of the web in the area of cutting by the cutting means is back-folded to form a gap through the web, applying a patch element to one surface of the web in registration with the gap, and controlling the patch element application in intermittent timed relation with the rate of feed of the web.

References Cited in the file of this patent UNITED STATES PATENTS 2,107,462 Wood Feb. 8, 1938 2,553,877 Smith et a1. May 27, 1951 3,051,370 Hanlon Aug. 28, 1962 

1. A METHOD OF MAKING A CONTAINER BODY WITH TEAR TO OPEN MEANS SIMULTANEOUSLY BUILT THEREINTO DURING THE WINDING STEP, SAID METHOD INCLUDING THE STEPS OF WINDING AN INNER WALL LAYER IN A SPIRAL WINDER, WINDING AN OUTER WALL LAYER OVER SAID INNER WALL LAYER, AND PRIOR TO WINDING SAID LAYERS TOGETHER, FEEDING A TEAR MEANS UPON THE OUTER WALL LAYER, FORMING A STARTING PULL TAB IN SAID OUTER WALL LAYER AND IN SAID TEAR MEANS, AND EXPOSING THE END OF THE PULL TAB BY FOLDING A PORTION OF SAID OUTER WALL LAYER TO FORM A GAP SPACE IN SAID OUTER WALL LAYER. 